FIG. 12 illustrates a hydraulic excavator 10, which is a work machine. The hydraulic excavator 10 includes a lower structure 11, an upper structure 12, a cab 13, a work equipment 14, and a power system 15 that includes an engine. The cab 13, the work equipment 14, and the power system 15 are mounted on the upper structure 12, which is rotatably mounted on the lower structure 11. The power system 15 is covered by a top cover 16, side doors 17, and other such components. For installation of these cover and side doors and other components, a frame is provided at the machine body. The top cover 16 and the side doors 17 are attached to the frame by hinges so as to be capable of opening and closing. Normally, the side doors 17 or other such components are secured in the closed state to the frame provided at the machine body by means of a latching device 18 (e.g. See Japanese Laid-open Patent Publication No. 2001-262618 (pages 3 to 4, and FIGS. 2 to 4) (“JP '610”)), Japanese Laid-open Patent Publication No. 2007-137183 (page 3, and FIGS. 3 to 5) and Japanese Laid-open Patent Publication No. 2007-170114 (pages 5 to 8, and FIGS. 2 to 7) (“JP '114”)).
As illustrated in FIG. 12, separate from the latching device 18, a shimmy stopping member 19 for preventing vertical vibration is attached to each side door 17. As illustrated in FIG. 13, the shimmy stopping members 19 serve to prevent vertical vibration of the side door 17 by respectively catching vertical vibration suppressors 19a, which are attached to the frame at the machine body.
Examples of conventional means to prevent such vertical vibration include a device for simultaneously stabilizing a portion where two doors overlap each other (e.g. See JP '618) and another device for fitting stoppers provided at the doors with stopper receivers that are provided at the frame at the machine body (e.g. See JP '114).